147P Serplulimab combined with chemotherapy in the neoadjuvant treatment of resectable oesophageal squamous cell carcinoma: A single-arm phase II trial

treatment.The primary endpoint was the pathologic complete response (pCR) rate; secondary endpoints included R0 resection rate, overall response rate (ORR), eventfree survival (EFS), disease-free survival (DFS), safety.Results: From November 2023 to June 2024, 15 patients were enrolled and completed neoadjuvant treatment; 2 patients were lost to follow-up, and 5 refused surgery.Among the 8 patients who underwent surgery, 1 (12.5%)achieved pCR, and all achieved R0 resection.Tumor regression grades (TRG) observed were TRG0 in 1 (12.5%),TRG2 in 5 (62.5%), and TRG3 in 2 (25.0%) patients.Of the 13 evaluable patients, 8 (62%) achieved partial response (PR) and 5 (38%) had stable disease (SD).ORR and DCR were 62% (8/13) and 100.0%(13/13), respectively.Treatment-related adverse events (TRAEs) occurred in 100% of patients, but no grade 3-5 TRAEs were observed.Toxicity and post-surgery complications were limited, and surgical feasibility was not impacted.Conclusions: Neoadjuvant adebrelimab combined with chemotherapy, followed by surgery and adjuvant treatment, demonstrated good efficacy and safety in patients with resectable locally advanced AEG, offering a promising treatment option for this patient population.Clinical trial identification: NCT06198465.